Control Your OS-X Keynote Presentation from iPhone

If you are on a Wifi and both your mac and iPhone can access it, you can
get free ride with controlling Keynote from your iPhone by using:
Keymote, which in part
uses Telekinesis
iPhoneRemote.

Telekinesis actually uses iPhone Safari and Ajax so you need to point
iPhone Safari to a specific address (https://192.168.74.104:5010/ by
default). You can bookmark it as iPhone shortcut on iPhone desktop
though, for easy launching.